Cycles baked AO too bright
Answer:
Thanks to Jerryno and Mentalist I understand now that the reason why the Cycles AO map is too bright is because unlike in Blender Render, materials in cycles don't affect AO bakes - rather a more physically correct lighting model is applied in cycles. 

Other Solutions:
Metalist gave me the following info/solution (unfortunately, I haven't tried either because I don't know how to get them to work in a batch bake addon I'm using):
- Cycles materials can be used in Blender Render
- It's possible to create a cavity map using the "Pointiness" property on the geometry node for the mesh, and combine that result with the AO map. 

I'm using an addon someone made a couple years ago to bake these AO (and normals), but it only works with cycles. I'll try to get help on converting it to work with Blender Render.  That, or I'll try to modify the addon to insert a semi transparent grey layer over the AO before it saves it out.